Don’t I need someone to schedule and release those jobs for someone to report against them? I don’t want to trouble someone with that extra responsibility… especially if we’re still not going to build exactly to that schedule… they are going to prioritize what’s needed first, which may or may not align with that MRP schedule.
If you don’t trust the schedule for the sub-assemblies, how can you trust the planning for the raw materials that you need to make it?
Also, there isn’t anything saying that you have to follow the dates on the jobs. You can just firm up all jobs, ignoring the dates, then people can pick the job they need to work on, and report against it.
You can do whatever you want. I’m just pointing out the logic error.
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I appreciate all your feedback. Thanks!
Do you plan phantom assemblies? Can you plan materials without planning phantoms?
We have never directly planned phantoms (you can’t). They get planned by association to the parent BOM - which we do plan. But due to how we are building this new product line, that won’t work. So I need to plan the lower level subassemblies. At some point, we cross from “the intent of the software” and “best practices” to “the best way to apply them to our specific situation”.
I believe we’ve gotten off track. I should probably mark this solved 
Is this the difference between Kanban Bin and Kanban Warehouse replenishment?
Same for Kanban here at PTI. Raw materials are still getting ordered.
What signals are they using to get them ordered?
Same signals as a phantom.
Phantom means that the materials are on an actual job. So you are making jobs then ignoring them and doing Kanban instead?
We use Kanban jobs extensively for a certain class of products and it works well. Input raw materials are all stock items and managed accordingly through min/max levels etc.
However, we have noticed an issue where there are phantoms in the method. The BOM is flattened and the lot controlled raw material inputs are entered by us. However, the actual issue is incorrect in such cases where the same raw material appears on more than one phantoms.
For eg. Mat A required 100 lbs
Mat A required 200 lbs
The above appear on the same BOM due to different phantoms involved. Now when we enter the issue 100 and 200 respectively the system accepts it. But the actual issue is either 100 or 200 lbs, depending on which one is entered last. This started happening since we moved onto 2021.1. We are testing 2022.2 and the issue is till there. Are you guys having any such issue.
I am going to raise it with Epicor soon.
Thanks
Vinay Kamboj
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I have an assembly A, then B, then C. If I get demand on the A, do you see suggestions just for B, or do you get suggestions for B and C? Or do I have to firm up each level and run MRP once for each level I’m planning?
It will do all levels if all of the levels have process MRP on.
Generally if you are using kanban it’s a “Pull” method, and you pull things up to the next station or hole as needed. When you have an empty hole, the process before produces what it needs to fill that empty hole.
MRP is a push system. When you have an order for a product, the order starts with buying the materials, then as the materials get there, the job is done for the subcomponents and then when those are done, the job for the top level is done.
So for the system to work as designed, you end with MRP the “push” and the beginning of the push starts at the end of the pull. So end with MRP, which starts pushing at the top level job. The Kanban starts at the subcomponent and “pulls” from materials as needed. The initial buy signal is a min/max setting on the stock.
You don’t want to “Push” MRP signals to buy the raw materials, then try to pull through Kanban, then go back to push. There is a clear line where it transfers from kanban to MRP. You can’t use MRP to plan the raw materials without having MRP first plan the sub-component jobs, even if they are unfirmed, they are still planned. If you make them some other way outside of the plan, (using a Kanban job) you also run the risk of your raw materials not having the correct plan to buy. If you fulfill the demand another way, you don’t know for sure that your MRP job that the system planned to satisfy the demand will be removed, so your MRP might have you buy more material than you need. This could happen is someone runs purchase suggestions without doing the full MRP run. Purchase suggestion will respond when inventory is used, and still has demand (the MRP job). But will not remove unfirmed jobs.
You can even set up the MRP jobs to backflush materials and labor just like a Kanban job would do. If you aren’t putting any thought into scheduling things date-wise, you can just firm the jobs that are already planned. The “work” in a scheduler is actually trying to make a realistic schedule. If you don’t care about the dates, just check the firm box and move on with your life. And if you don’t trust that MRP is planning the correct quantities for the sub-components, how can you trust that it’s planning the right raw materials?
Also, keep in mind “MRP” and “Kanban” Are not Epicor specific ideas. These are industry standard manufacturing strategies. If you’re curious, do some research on how Kanban is designed to work.
I wish we could upload the whole slide deck from the 2018 insights session on kanban (side note, I love @hkeric.wci)…
It would illustrate all of the great posts you’ve made here and help others understand why kanban pretty much replaces MRP- but absolutely requires you to be on your game and have complete control and understanding of your lead times, tack times, cycle times, etc…
However, Brandon, I can’t really put it in the same words as it was described to me, but the presenter did show how if you leave process MRP checked, some people would use those suggestions as a “feel good” indicator. Again, I am not doing the presenter justice, but the presenter went off from the slides and/or added in some slides demonstrating how they left MRP on for notational purposes only.
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I could see that being valid. As long as you understand that MRP is showing you some sort of suggestions, and might give you a warning if they are way off from what you are expecting. And that you understand that you are no longer relying on MRP giving you the plan to buy the exact stuff you need at the exact right time. You don’t really want to use Kanban for stuff you only buy when you have orders driving the requirements. It works great for things like steel, hardware, common components, common subassemblies, etc.
I wanted to note: I hope I don’t come across as argumentative. This is great conversation. This is what I went to college for and did before I became a “Developer”, so discussing manufacturing strategies is interesting to me.
Thanks @Mark_Wonsil . and @dr_dan for engaging in the discussion.
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Nah you were crystal clear and it was awesome of you to take the time to write all of this. Lean principles are not straightforward to teach although they mean to make things simple haha
It’s one of those things that once you see it all click you get it, but it’s hard to picture when you first start learning about some of the concepts.
A good way to get it “Click” is to think of Kanban like a restaurant.
Imaging trying to run only MRP at a restaurant.
The customer comes in and sits down. The waiter takes their order, and the order gets loaded into the computer. The computer then makes the PO’s for the lettuce, the meat, the bread, and someone has to go and purchase those things. Once they get purchased and brought to the kitchen, they can get made. The customer had to wait 2 days to get their food, but you didn’t have to have anything stocked.
Running Kanban prefills the supply line. You have a stock of food in the fridge. During the dinner hour, that stock in used, and at the end of the night, they order for the next day to fill back up the predetermined minimum level. You do that so when the customer comes in and orders, the cook can start cooking right away, and they get their food in 15 minutes or so.
The order is still MRP, but the “Push” starts when the waiter sends the order to the back. The ingredients are all “Pulled” up to the meeting point of the cook and you have one handoff between Kanban and MRP.
The goal of Kanban is to reduce the amount of time from order to fulfillment. When done to it’s fullest extent, you don’t have time to wait for materials to be ordered from the MRP run. You pull from the stock that you have on hand. Then the “holes” that you created are refilled so that when more orders come in, you have more stock on hand.
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I love the discussion also. I did not go to school for this.
When explaining my plan to our Quality supervisor, I literally used the restaurant analogy. I used to manage a restaurant while in college and I harkened Kanban to the same thing. You know how many of each thing you’re supposed to have on the shelf and if there’s less, you order more.
This is really going to be an adventure. What we’re trying to do goes against how we’ve done things forever. Pray for me haha.
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